Many of the physical properties investigated in this research program were significantly enhanced by the addition of ground recycled rubber to the asphalt cement binder. These asphalt-rubber mixtures were found to act quite differently from traditional, unmodified asphalt mixtures. However, these results indicate that improved pavement performance can be achieved with asphalt-rubber binder if the design and construction criteria are changed to reflect the unique physical characteristics imparted by these special binders.